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    <title>Document</title>
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<script>
//   99 乘法表
// 外层 for 表示 行数
   for(var i = 1 ; i <= 9 ; i++){
       // 内层for 列数 
      for(var j = 1 ; j <= i ; j++ ){
         document.write(i+" * "+j +" = "+(i*j)+"&nbsp;&nbsp;&nbsp;");
      }
      document.write("<br/>");
   }

   var arr = [1,3,5,7,3,2,5,3];

</script>
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